KR102348954B1 - De-emulsifying additive compositions, and uses thereof, and methods of de-emulsifying - Google Patents

Abstract

The present invention relates to a de-emulsifying additive composition for de-emulsifying a water-in-oil emulsion resulting from washing water in crude oil, said composition comprising (a) at least one de-emulsifying agent (component (a)); and (b) a compound selected from the group comprising glyoxal, neutralized glyoxal, glyoxal derivatives and mixtures thereof (component (b)), and (c) further phosphoric acid (component (c) ) is included. The present invention also relates to a method of using the de-emulsifying additive composition of the present invention for the de-emulsifying of a water-in-oil emulsion resulting from washing water in crude oil. The present invention also relates to a method for de-emulsifying a water-in-oil emulsion resulting from washing water in crude oil by using the de-emulsifying additive composition of the present invention.

Description

De-emulsifying additive compositions, and uses thereof, and methods of de-emulsifying

The present invention relates to a demulsifying additive composition for the demulsification of water-in-oil emulsions.

In particular, the present invention relates to a de-emulsifying additive composition for de-emulsifying a water-in-oil emulsion generated by mixing washing water and crude oil, more specifically, by mixing washing water and crude oil in a desalting apparatus of an oil refinery. is about

More particularly, the present invention relates to a de-emulsifying additive composition for de-emulsifying a water-in-oil emulsion generated by mixing washing water and crude oil in a desalting apparatus of an oil refinery, wherein the de-emulsifying additive composition comprises at least

(a) one or more demulsifiers;

(b) a compound selected from the group comprising glyoxal, neutralized glyoxal and mixtures thereof

a combination of; and

(c) further comprising phosphoric acid.

In one embodiment, the present invention provides a water-in-oil emulsion, in particular a water-in-oil emulsion generated by mixing washing water and crude oil, more particularly washing water in a desalting apparatus of an oil refinery by using the de-emulsifying additive composition of the present invention. It relates to a method of de-emulsifying a water-in-oil emulsion generated by mixing crude oil and oil.

In another embodiment, the present invention relates to a water-in-oil water emulsion, in particular a water-in-oil emulsion generated by mixing washing water and crude oil, more particularly water generated by mixing washing water and crude oil in a desalting unit of an oil refinery. - To a method of using the de-emulsifying additive composition of the present invention for de-emulsifying an in-oil emulsion.

Water-in-oil emulsions form in a variety of industrial operations, resulting in substantial losses of various industrial components, including difficulties in oil separation. Thus, breaking the water-in-oil emulsion during oil processing is a requirement of industry, particularly the crude oil refining industry, where wastewater is mixed with crude oil in the desalting unit of an oil refinery to form a water-in-oil emulsion.

Currently, water-in-oil emulsions generated by mixing wash water and crude oil are destroyed by adding a demulsifier to the wash water.

The main problem with using de-emulsifiers is that they are used in larger quantities and are continuously required throughout the processing of crude oil, which significantly increases the cost of crude oil processing.

Another problem with using de-emulsifiers is that they are expensive and also significantly increase the cost of processing the crude oil.

More importantly, currently used demulsifiers are condensation products of nonyl phenols, and there is currently a need to reduce consumption of nonyl phenols in view of their cost and adverse environmental impact.

Invention Needs:

Accordingly, where total removal is not possible, it is desired to reduce the requirements of the demulsifier so that the above-mentioned problems of the use of the demulsifier can be minimized, at least without loss or sacrifice of the industrial output of the crude oil processing equipment.

Therefore, the present invention

i) an improved and effective de-emulsifying additive composition for de-emulsifying water-in-oil emulsions, and

ii) a method of using the de-emulsifying additive composition of the present invention for de-emulsifying a water-in-oil emulsion, and

iii) A method of de-emulsifying a water-in-oil emulsion by using the de-emulsifying additive composition of the present invention

It aims to provide a solution to the existing industrial problems by providing.

Therefore, the main object of the present invention is

i) a water-in-oil emulsion, in particular a water-in-oil emulsion generated by mixing washing water and crude oil, more particularly a water-in-oil emulsion generated by mixing washing water and crude oil in a desalting unit of an oil refinery; De-emulsifying additive composition for de-emulsifying

is to provide

Accordingly, another object of the present invention is

ii) a water-in-oil emulsion, in particular a water-in-oil emulsion generated by mixing wash water and crude oil, more particularly for mixing wash water and crude oil in a desalting apparatus of an oil refinery by using the de-emulsifying additive composition of the present invention Demulsification method of water-in-oil emulsion generated by

is to provide

Accordingly, another object of the present invention is

iii) a water-in-oil emulsion, in particular a water-in-oil emulsion generated by mixing washing water and crude oil, more particularly a water-in-oil emulsion generated by mixing washing water and crude oil in a desalting unit of an oil refinery; Methods of Using the De-emulsifying Additive Composition of the Present Invention for De-emulsifying

is to provide

Accordingly, it is an object of the present invention to reduce the amount of currently used demulsifiers, which are condensation products of nonyl phenols, and thus reduce the consumption of nonyl phenols or condensation products of nonyl phenols, thereby reducing processing costs and associated environmental adverse effects. For de-emulsification of a water-in-oil emulsion, preferably a water-in-oil emulsion generated by mixing wash water and crude oil, more preferably in the desalting apparatus of an oil refinery, the washing water and crude oil To provide a de-emulsifying additive composition for de-emulsifying a water-in-oil emulsion generated by mixing.

Other objects and advantages of the present invention will become more apparent from the following description when read in conjunction with the Examples, which are not intended to limit the scope of the present invention.

In order to overcome the above-mentioned industrial problems of the prior art and achieve the above-mentioned objects of the present invention, the present inventors have

(a) one or more demulsifiers (which may also be referred to as component (a)); and

(b) a compound (which may also be referred to as component (b)) selected from the group comprising glyoxal, neutralized glyoxal, glyoxal derivatives and mixtures thereof, and

(c) the composition further comprising phosphoric acid (which may also be referred to as component (c)), surprisingly and unexpectedly, significantly improves the de-emulsifying efficiency of the de-emulsifying agent (component (a)), thereby It has been found to significantly reduce the requirement, which significantly reduces the processing cost of the crude oil, and the associated adverse environmental impacts.

The inventors also found that, surprisingly and unexpectedly, the composition of the present invention comprising the combination of component (a), component (b), and component (c) comprises:

a composition comprising the combination of components (a) and (b), and

a composition comprising the combination of components (a) and (c)

was found to significantly improve the demulsification efficiency of

In addition, since glyoxal and neutralized glyoxal are less expensive than de-emulsifiers, it also significantly reduces the processing cost of crude oil.

Accordingly, the present invention relates to a de-emulsifying additive composition for de-emulsifying a water-in-oil emulsion generated by washing water in crude oil, the composition comprising:

(a) one or more demulsifiers (component (a)); and

(b) a compound selected from the group comprising glyoxal, glyoxal derivatives, neutralized glyoxal, and mixtures thereof (component (b));

includes, and

(c) further comprising phosphoric acid (component (c)).

The inventors also include combinations of components (a) and (b), or combinations of components (a) and (b), and (c), wherein

Component (b) is

glycolic acid;

glyoxylic acid;

citric acid; or

maleic anhydride

comprising one or more of, and

It has been found that component (c) shows no improvement in the de-emulsification efficiency of the composition comprising phosphoric acid, wherein the composition consists of component (a) of the present invention.

According to one of the embodiments of the present invention, the composition of the present invention comprises

glycolic acid;

glyoxylic acid;

citric acid; or

maleic anhydride

does not contain one or more of

According to the present invention, the neutralized glyoxal is glyoxal having a neutral to basic pH. The inventors have observed that glyoxal is very acidic and thus can cause corrosion. Therefore, neutralizing glyoxal until the pH of glyoxal becomes neutral to basic avoids corrosion of crude oil processing equipment, and still improves the de-emulsification efficiency of the de-emulsifier.

According to the invention, neutralized glyoxal is obtained by neutralizing glyoxal with an amine or an alkaline medium.

According to the present invention, the amine may comprise (or contain) triethanol amine (TEA).

According to the present invention, the alkaline medium may comprise (or contain) an aqueous sodium hydroxide solution.

According to the present invention, neutralized glyoxal may also comprise (or contain) derivatives of neutralized glyoxal. Thus, in the present invention, the term "neutralized glyoxal" or the term "neutralized derivative of glyoxal" has one and the same meaning unless otherwise specified.

According to the present invention, neutral to basic pH includes a pH in the range of about 7 to about 12.

According to the present invention, the glyoxal derivative may comprise (or contain) a methanol, ethanol, butanol, or ethylene glycol derivative of glyoxal, or a mixture thereof.

According to one preferred embodiment of the invention, the demulsifier is

i) nonyl phenol and amyl phenol, and formaldehyde;

ii) nonyl phenol and butyl phenol, and formaldehyde;

iii) nonyl phenol and formaldehyde;

iv) amyl phenol and formaldehyde;

v) butyl phenol and formaldehyde;

vi) alkyl phenols and formaldehyde; and

vii) mixtures thereof

oxyalkylated condensation products of

According to another preferred embodiment of the present invention, the demulsifier is

i) cardanol, nonyl phenol and amyl phenol, and formaldehyde;

ii) cardanol, nonyl phenol and butyl phenol, and formaldehyde;

iii) cardanol, nonyl phenol and formaldehyde;

iv) cardanol, amyl phenol and formaldehyde;

v) cardanol, butyl phenol and formaldehyde;

vi) cardanol, alkyl phenol and formaldehyde; and

vii) mixtures thereof

oxyalkylated condensation products of

According to one preferred embodiment of the invention, the demulsifier is

i) oxyalkylated nonyl phenol and amyl phenol formaldehyde copolymers;

ii) oxyalkylated nonyl phenol and butyl phenol formaldehyde copolymers;

iii) an oxyalkylated nonyl phenol formaldehyde polymer;

iv) an oxyalkylated amyl phenol formaldehyde polymer;

v) oxyalkylated butyl phenol formaldehyde polymers;

vi) oxyalkylated alkyl phenol formaldehyde polymers; and

vii) mixtures thereof

is selected from the group comprising

According to one preferred embodiment of the invention, the demulsifier is

i) oxyalkylated cardanol, nonyl phenol and amyl phenol, and formaldehyde copolymers;

ii) oxyalkylated cardanol, nonyl phenol and butyl phenol, and formaldehyde copolymers;

iii) oxyalkylated cardanol, nonyl phenol and formaldehyde polymers;

iv) oxyalkylated cardanol, amyl phenol and formaldehyde polymers;

v) oxyalkylated cardanol, butyl phenol and formaldehyde polymers;

vi) oxyalkylated cardanol, alkyl phenol and formaldehyde polymers; and

vii) mixtures thereof

It may be selected from the group comprising

According to one preferred embodiment of the present invention, the oxyalkylated product is an ethylene oxide derivative, a propylene oxide derivative, a butylene oxide derivative or a mixture thereof. According to one preferred embodiment of the present invention, the oxyalkylated product is an oxyalkylated copolymer or an oxyalkylated polymer or an oxyalkylated resin. According to one preferred embodiment of the present invention, the oxyalkylated product is a base catalyzed oxyalkylated copolymer of one or more of the above phenolic compounds (i.e. cardanol, nonyl phenol, butyl phenol, amyl phenol, alkyl phenol) and formaldehyde. or a base catalyzed oxyalkylated polymer or a base catalyzed oxyalkylated resin. According to one preferred embodiment of the present invention, the oxyalkylated product is an oxyalkylated phenol formaldehyde resin, an oxyalkylated phenol formaldehyde polymer, or an oxyalkylated phenol formaldehyde copolymer.

According to one embodiment of the present invention, the phenolic reactant comprises an alkyl phenol comprising an alkyl group. According to one embodiment of the present invention, the alkyl group contains from about 1 to about 20 carbon atoms. According to one of the embodiments of the present invention, the substitution may be a butyl, amyl, nonyl, hexyl, octyl, isooctyl, decyl or dodecyl group.

The term "copolymer" refers to a polymer prepared from two different phenols, the term "polymer" refers to a polymer prepared from one phenol, and resins are intended to include polymers and copolymers. It is intended

According to one embodiment of the present invention, the reaction of an alkyl phenol formaldehyde resin with an alkylene oxide forms a high molecular weight oxyalkylated alkyl phenol formaldehyde resin.

According to one embodiment of the present invention, the alkylene oxide comprises ethylene oxide, propylene oxide, butylene oxide or mixtures thereof, preferably the alkylene oxide comprises ethylene oxide, propylene oxide, or mixtures thereof.

According to one preferred embodiment of the present invention, the molecular weight of the demulsifier of the present invention is from about 1000 to about 20000 Daltons, preferably about 2000 as determined by gel permeation chromatography (GPC) using tetrahydrofuran (THF) as solvent. to about 15000 Daltons, more preferably from about 2000 to about 10000 Daltons.

According to one embodiment of the present invention, the average molecular weight of the demulsifier of the present invention is from about 1000 to about 20000 Daltons, preferably about It may range from 2000 to about 15000 Daltons, more preferably from about 2000 to 10000 Daltons.

According to the invention, the composition depends on the nature of the water-in-oil emulsion to be treated.

a) component (a) in an amount ranging from about 99.1% to about 0.1% by weight of the total composition;

b) component (b) in an amount ranging from about 0.1% to about 99.1% by weight of the total composition; and

c) component (c) in an amount ranging from about 0.1% to about 99.1% by weight of the total composition

includes

It may be noted that, according to the present invention, the additive composition can be added to the crude oil phase or added to the desalter where the wash water is mixed with the crude oil to form a water-in-oil emulsion.

It may also be noted that the scope of the present invention is not limited to crude oil or wash water.

Accordingly, in another embodiment, the present invention relates to a water-in-oil emulsion, in particular a water-in-oil emulsion formed by mixing washing water and crude oil, more particularly water formed by mixing washing water and crude oil in a desalting unit of an oil refinery. - relates to a method for de-emulsifying an in-oil emulsion, wherein a water-in-oil emulsion formed due to mixing of washing water with crude oil is treated with a currently provided de-emulsifying additive composition.

Accordingly, in another embodiment, the present invention also relates to a water-in-oil emulsion, in particular a water-in-oil emulsion formed by mixing washing water and crude oil, more particularly formed by mixing washing water and crude oil in a desalting unit of an oil refinery. A method of using the currently provided de-emulsifying additive composition for the de-emulsifying of a water-in-oil emulsion, wherein the de-emulsifying additive composition currently provided for a water-in-oil emulsion formed resulting from mixing of wash water with crude oil. It relates to a method of using an additive, presently provided de-emulsifying additive composition. It may be noted that the scope of the present invention is not limited to the amount of the additive composition of the present invention that must be added in an amount sufficient for de-emulsification of a water-in-oil emulsion.

The present invention is now described with reference to the following examples, which are included not to limit the scope of the invention but to illustrate the advantages of the invention over the prior art.

Example:

The following examples were carried out under the following conditions:

PED No 1315

Crude oil: raw material

API: 28.1

Washing water: 5% (HMEL, ID 443), pH-8.1

Mixing temperature: 55℃

Mixing time: 2 minutes

Temperature: 130℃

Voltage: 3KV for 8 minutes

In the examples below, the following compositions were tested for their de-emulsification efficiency.

1. Component (a) is a demulsifier which is a 50% active nonylphenol formaldehyde ethoxylate resin (or may be a base catalyzed nonylphenol formaldehyde resin);

2. Component (b) of the present invention is glyoxal or neutralized glyoxal, wherein glyoxal has been neutralized with triethanol amine (TEA);

3. Component (c) of the present invention is phosphoric acid;

4. The comparative component may be selected from glycolic acid, glyoxylic acid, citric acid and maleic anhydride. In the following experiments, they were identified as follows and were taken in DM (demineralized water) at 14% by weight:

Comparative component (b1) is glycolic acid (40%);

Comparative component (b2) is glyoxylic acid (40%);

Comparative component (b3) is citric acid (40%);

The comparative component (b4) is maleic anhydride (40%).

5. The comparative composition does not include the combination of components (b) and (c) of the present invention.

A 'blank' is one without any additives.

Table-I

In Table-I, the dose '10+3' indicates that the additive contains 10 ppm of component (a) and 3 ppm of comparative component (b1), and the like.

However, in Table-I, the 'composition of the present invention' comprises 10 ppm of component (a) and 3 ppm of [component (b) + component (c)], wherein [component (b) + component (c)] contains component (b) which is glyoxal (40%) and _{component (c) which is H 3} PO ₄ (85%) in DM (demineralized water) in a weight ratio of 14/0.43/85.57.

As can be seen in Table I above, the composition of the present invention exhibits an 84% efficiency compared to the 56% or 74% efficiency of the comparative composition.

Table-II

In Table-II, the dose '10+3' indicates that the additive is 10 ppm of component (a) and 3 ppm of the second component, i.e., comparative component (b1), comparative composition (B), comparative component (b2), and comparative composition. (C), comparative component (b3), comparative composition (D), comparative component (b4) and comparative composition (E) are shown to be included.

In Tables I and II above, the various components have the following composition:

component (a) is a 50% active nonyl phenol formaldehyde ethoxylate resin (oxyalkylated condensation product);

component (b) comprises glyoxal (40%) in 14% DM water;

component (c) comprises H ₃ PO ₄ (85%) in 0.43% DM water;

The composition of the present invention contains, in addition to component (a), component (b) which is glyoxal (40%) and _{component (c) which is H 3} PO ₄ (85%) in DM water in a weight ratio of 14/0.43/85.57 do;

Comparative component (b1) is glycolic acid (40%) in 14% DM water;

Comparative composition (B) comprises component (b1) which is glycolic acid (40%) and _{component (c) which is H 3} PO ₄ (85%) in DM water in a weight ratio of 14/0.43/85.57;

Comparative component (b2) is glyoxylic acid (40%) in 14% by weight DM water;

Comparative composition (C) comprises comparative component (b2) which is glyoxylic acid (40%) and _{component (c) which is H 3} PO ₄ (85%) in DM water in a weight ratio of 14/0.43/85.57;

Comparative component (b3) is citric acid (40%) in DM water at 14% by weight;

Comparative composition (D) comprises comparative component (b3) which is citric acid (40%) and _{component (c) which is H 3} PO ₄ (85%) in DM water in a weight ratio of 14/0.43/85.57;

Comparative component (b4) is maleic anhydride (40%) in 14% by weight DM water;

Comparative composition (E) comprises comparative component (b4) which is maleic anhydride (40%) and _{component (c) which is H 3} PO ₄ (85%) in DM water in a weight ratio of 14/0.43/85.57;

As can be observed from Table II above, all comparative compositions show only 56% or 60% efficiency.

Table-III

In Table 3, the mixing time was 2 minutes, the mixing temperature was 55° C., component (b) was 0.9 ppm glyoxal (40%) in DM water, and 0.9 ppm component (c) was 0.87 ppm in DM. of glyoxal (40%) and 0.03 ppm H ₃ PO ₄ (85%) (ie, 97 wt % glyoxal (40%) and 3 wt % H ₃ PO ₄ (85%) in DM) and; and component (a) is a 50% active ethoxylated nonyl phenol cardanol formaldehyde resin, which is an ethoxylated condensation product of 90% by weight nonyl phenol and 10% by weight cardanol.

As can be observed from Table III above, the composition of the present invention exhibits 90% efficiency compared to 56% or 74% efficiency of the comparative composition.

Table-IV

In Table IV, the mixing time was also 2 minutes, the mixing temperature was also 55° C., component (b) was 0.9 ppm glyoxal (40%) in DM water, and 0.9 ppm component (c) was 0.846 in DM. ppm glyoxal (40%) and 0.054 ppm H ₃ PO ₄ (85%) (ie, 94 wt % glyoxal (40%) and 6 wt % H ₃ PO ₄ (85%) in DM) includes; and component (a) is a 50% active ethoxylated nonyl phenol para tertiary amyl phenol formaldehyde resin, which is an ethoxylated condensation product of 50 wt % nonyl phenol and 50 wt % para tertiary amyl phenol.

As can be observed from Table IV above, the composition of the present invention exhibits an 84% efficiency compared to the 60% or 74% efficiency of the comparative composition.

Table-V

In Table V, the mixing time was also 2 minutes, the mixing temperature was also 55° C., component (b) was 1.2 ppm glyoxal (40%) in DM water, and 1.2 ppm component (c) was 1.164 in DM. ppm glyoxal (40%) and 0.036 ppm H ₃ PO ₄ (85%) (ie, 97 wt % glyoxal (40%) and 3 wt % H ₃ PO ₄ (85%) in DM) includes; and component (a) is a 50% active ethoxylated nonyl phenol para tertiary butyl phenol formaldehyde resin, which is an ethoxylated condensation product of 90 wt % nonyl phenol and 10 wt % para tertiary butyl phenol.

As can be observed from Table IV above, the composition of the present invention exhibits an 84% efficiency compared to the 60% or 74% efficiency of the comparative composition.

In the above examples, the additive composition of the present invention and the prior art or comparative additive composition were added to a water-in-oil emulsion of water and crude oil formed after mixing of water and crude oil.

The above experimental results confirm the above-mentioned surprising and unexpected technical advantages of the present invention. In particular, these experiments confirm that the inventive additive composition comprising component (a), inventive component (b) and inventive component (c) exhibits surprising and unexpected technical advantages.

It may be noted that the term "about" as used herein is not intended to broaden the scope of the claimed invention, but is incorporated merely to cover the permissible empirical error of the technical field of the present invention.

Claims (13)

A de-emulsifying additive composition comprising:
(a) a first component which is an oxyalkylated alkyl phenol formaldehyde polymer or copolymer or resin, or at least one demulsifier comprising an oxyalkylated condensation product of at least one alkyl phenol and formaldehyde;
(b) a second component selected from the group comprising glyoxal, glyoxal derivatives, neutralized glyoxal, and mixtures thereof; and
(c) a third component that is phosphoric acid;
Neutralized glyoxal is glyoxal having a neutral to basic pH;
wherein the glyoxal derivative is selected from methanol, ethanol, butanol, or ethylene glycol derivatives of glyoxal, or mixtures thereof.
According to claim 1,
wherein the neutralized glyoxal is glyoxal having a neutral to basic pH in the range of 7 to 12.
According to claim 1,
demulsifier
i) nonyl phenol and amyl phenol, and formaldehyde;
ii) nonyl phenol and butyl phenol, and formaldehyde;
iii) nonyl phenol and formaldehyde;
iv) amyl phenol and formaldehyde;
v) butyl phenol and formaldehyde;
vi) alkyl phenols and formaldehyde; and
vii) mixtures thereof
A de-emulsifying additive composition selected from the group comprising an oxyalkylated condensation product of
According to claim 1,
demulsifier
i) cardanol, nonyl phenol and amyl phenol, and formaldehyde;
ii) cardanol, nonyl phenol and butyl phenol, and formaldehyde;
iii) cardanol, nonyl phenol and formaldehyde;
iv) cardanol, amyl phenol and formaldehyde;
v) cardanol, butyl phenol and formaldehyde;
vi) cardanol, alkyl phenol and formaldehyde; and
vii) mixtures thereof
A de-emulsifying additive composition selected from the group comprising an oxyalkylated condensation product of
According to claim 1,
wherein the oxyalkylation is a derivative of ethylene oxide, propylene oxide, or mixtures thereof.
According to claim 1,
demulsifier
i) oxyalkylated nonyl phenol and amyl phenol formaldehyde copolymers;
ii) oxyalkylated nonyl phenol and butyl phenol formaldehyde copolymers;
iii) an oxyalkylated nonyl phenol formaldehyde polymer;
iv) an oxyalkylated amyl phenol formaldehyde polymer;
v) oxyalkylated butyl phenol formaldehyde polymers;
vi) oxyalkylated alkyl phenol formaldehyde polymers; and
vii) mixtures thereof
A de-emulsifying additive composition selected from the group comprising
According to claim 1,
demulsifier
i) oxyalkylated cardanol, nonyl phenol and amyl phenol, and formaldehyde copolymers;
ii) oxyalkylated cardanol, nonyl phenol and butyl phenol, and formaldehyde copolymers;
iii) oxyalkylated cardanol, nonyl phenol and formaldehyde polymers;
iv) oxyalkylated cardanol, amyl phenol and formaldehyde polymers;
v) oxyalkylated cardanol, butyl phenol and formaldehyde polymers;
vi) oxyalkylated cardanol, alkyl phenol and formaldehyde polymers; and
vii) mixtures thereof
A de-emulsifying additive composition selected from the group comprising:
According to claim 1,
The composition depends on the nature of the water-in-oil emulsion to be treated.
a) a first component in an amount ranging from 99.1% to 0.1% by weight of the total composition;
b) a second component in an amount ranging from 0.1% to 99.1% by weight of the total composition; and
c) the third component in an amount ranging from 0.1% to 99.1% by weight of the total composition
A de-emulsifying additive composition comprising a.
According to claim 1,
wherein the molecular weight of the demulsifier is in the range of 1000 to 20000 Daltons as measured by gel permeation chromatography (GPC) using tetrahydrofuran (THF) as a solvent.
According to claim 1,
the composition
(i) glycolic acid;
(ii) glyoxylic acid;
(iii) citric acid; and
(iv) maleic anhydride
A de-emulsifying additive composition that does not include
11. A method of de-emulsifying a water-in-oil emulsion, wherein the water-in-oil emulsion is treated with a de-emulsifying additive composition as claimed in any one of claims 1-10. Way.
11. A method of using the de-emulsifying additive composition as claimed in any one of claims 1 to 10 for the de-emulsification of a water-in-oil emulsion. delete